Bill Ackman, the hedge fund titan and longtime Donald Trump supporter, has called for a 90-day halt to the U.S. tariff escalation set to take effect on April 9, as markets continue to feel the effects of recently implemented US trade policy.

Without the halt, Ackman warned, the country could be headed for an “economic nuclear winter” that would crush business confidence, halt investment, and lead to mass layoffs. 

“This is not what we voted for,” Ackman wrote on X, formerly Twitter. “Business is a confidence game. The president is losing the confidence of business leaders around the globe.”

Ackman’s plea follows President Trump’s announcement that the U.S. would impose a 25% tariff on all foreign-made automobiles, a 10% “minimum baseline tariff” on imports, and new “reciprocal tariffs” targeting countries with levies on American goods. 

“Our country and its taxpayers have been ripped off for more than 50 years,” Trump declared from the White House Rose Garden last week. “But it’s not going to happen anymore.”

The administration’s formula, trade deficit divided by imports, was quickly flagged by economists as overly simplistic and likely to backfire.

“By placing massive and disproportionate tariffs on our friends and our enemies alike… we are in the process of destroying confidence in our country as a trading partner,” Ackman said in his post.

That eroding confidence is now playing out in markets, especially crypto.

Bitcoin (BTC) fell to $77,300 on Monday, down 7.6% over 24 hours, erasing nearly $70 billion in market cap.  Ethereum (ETH) has slipped to $1,555, down 14% in a single day, according to CoinGecko data.

The drop follows a sharp but brief Bitcoin rally last Thursday, when the coin spiked to $87,800 during Trump’s tariff announcement before retreating sharply.

“The market is easily manipulated in its current state,” Tracy Jin, COO of MEXC Exchange, told Decrypt. “This carries the threat of new disappointments… and this will call into question the status of Bitcoin as a safe haven asset, which may lead to an even sharper outflow of funds from the ETF.”

According to Jin, a negative scenario appears more likely with Bitcoin dropping to the “$52,000–$56,000 range” by summer. Ethereum, facing structural challenges beyond tariffs, may fare even worse, she said.

Edited by Sebastian Sinclair